Dental instrument



l. E. REID AND C. KIENLE.

DENTAL INSTRUMENT.

APPLICATION FILED MM2?, Isls.

Patented Apr. 6, 1920.

W/m/Ess JAMES ERNEST REID, er Mouans-row PHILADELPHIA, rEIInsri-ivnnra;

111, NEVI JERSEY, .E11-LII? CHARLES KIENLE, OF

SAB FLIENLE .LSSGNOR TO SAID REID.

DENTAL NSTRMENT.

Specification of Letters Patent.

.a-tented Apr. 6, 1920.

Application filed May 2'?, 1919. Serial No. 390,158.

To all whom t may concern.'

Be it known that we, JAMES E. REID, a citizen of the United States, residing at Moorestown, Burlington county, of New Jersey, and CHARLES KIENLE, citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have jointly invented a certain new and useful Dental instrument, of which the following is a specification.

The principal objects of the present invention are, rst, to provide a dental instrument in .vhich the electric current that heats the tool proper can be conveniently and readily turned on and off manually, and is turned olf automatically when the instrument is hung up; second, to simplify and improve the construction and operation of the instrument; third, to provide for the ready removal of the tool and its heater and for the replacement of the heater; fourth, to facilitate the making of repairs or renewals, and fifth, to provide for regulating the heat from the hand-piece of the instrument.

The invention will be claimed at the end hereof, but will be first described in connection with the embodiment of it selected from other embodiments for the sake of illustration in the accompanying drawings, forming part hereof, and in which- Figure 1, is a side view of an instrument embodying features of the invention.

Fig. 2, is a central sectional view, drawn to an enlarged scale, of the front or outer end part of the instrument.

Fig. 8, is a view with the outer end of the hand-piece in section and with the interior parts in elevation, and

Fig. t, is a similar view of the inner end part of the instrument shown in Fig. 3.

In the drawings, 1 is a tubular hand-piece slotted at 2, and provided at its rear end with an inlet 3 for the cable 1, carrying the leads 5 and 6. At the front end the handpiece is provided with a thimble 7, for a purpose to be described. There is a frame arranged in the hand-piece and it consists of a conductor 8, provided with front and rear blocks 9 and 10 having confronting bridge contacts 11 and 12 of the spring linger variety. 13, is a traveler movable on the conductor 8, and provided with an insulated bridge piece 13a, cooperating with the contacts 11 and 12 to span them and provide a path for current and to disconnect them and interrupt the path for current. 14:, is a finger piece, shown in the form of a ring, slidable on the hand-piece 1, and connected with the traveler 13 by a removable screw or pin 15, working in the slot 2. 16 and 17 are heater contacts, of the springfinger variety, projecting from the front block 9. rl"he contacts 17 are connected with the conductor S as by means of a cross-connection 18. 19, is a hollow tool shank provided internally with a heating coil 20, and detachahly mounted in the thimble 7, with the heater terminals 21 and 22 in detachabie engagement with the heater contacts 1G and 17. The path for current may be traced, F 2, from 5, to contacts-12, to bridge 13a, to contacts 11 and 16, to 21, through heater 20, to terminal 22, contact 17, cross-piece 18, conductor S and lead 6.

The position of the bridge piece 13@L is determined by the position of the lingen piece 14, when the latter is in the position shown in Fig. 2 the circuit is closed and the heater 2O is on; when the linger-piece 14 is in the position shown in Fig. 3, the circuit is open and theheater is off. The depressions 23 and 2%: servevin cooperation with the contacts 11, as detents to prevent accidental movement of the bridge-piece 13,

Current is easily turned on and off to regulate the temperature of the heater 20, by simply moving the nger-piece 14, and this can be done without interfering with the manipulation of the instrument. Again when the instrument is hung up in the usual fork A., Fig. 1, the tines of the latter' engage the linger-piece 14 and the .veight of the instrument or the slight downward pressure given to it causes it to drop and so move the bridge 13, into the position shown in Fig. 3, with the result that the path for the circuitis automatically broken. It is an advantage of the described instrument that the tool shank 19, heater 20, and terminals 21 and 22 can be removed or unscrewed from the thimble 7, as unitary structure, and then the heater can be readily replaced by unscrewing` 21 from 19; again the interior mechanism can be readily inserted and withdraw from the tubular hand-piece in assembled condition.

1f desired av rheostat operable from the hand-piece may be provided in addition to the parts described. 1n such case, Figs. 3 and 4.-, the block 10, with which the contacts l2 are connected, is of conducting inaterial and the conductor 8 is insulated from it. An extension 23, of the block 10, carries an insulated rheostat coil 24, one end of which is connected with the lead 5. 25, is the movable contact element of the rheostat and it is provided with a button 26, afforded sliding movement in an opening 27, through the hand-piece. By sliding the button 26, more or less resistance is interposed in the circuit so that the heat of the tool can be regulated, and this can be done conveniently by the operator.

Ve do not limit the invention in matters of detail and arrangement, but we claim:

1. A dental instrument comprising the combination of a tubular slotted hand-piece having leads through its rear end, a frame arranged in the hand-piece and consisting of a conductor provided with front and rear insulating blocks having confronting bridgecontacts, a traveler movable on the conductor and provided with an insulated bridge-piece coperating with said contacts, a finger-piece slidable on the hand-piece and connected with the traveler through the slot of the hand piece, heater contacts on the front block, and a tool shank provided with a heater and detachably mounted on the front end of the hand piece and having the heater terminals in detachable engagement with the heater contacts, substantially as described.

A2. A dental ,instrument vcomlprising in combination, a tubular hand-piece, a heater at one end thereof, spaced contacts mounted. in the hand-piece and current connections therefor, a bridge movable endwise in and of the hand-piece to span and to disconnect said contacts, and a slide movable endwise of and on the hand-piece and connected with the bridge, substantially as described.

3. In a dental instrument the combination of a conductor, spaced blocks carried by the conductor and provided with confronting contacts, a traveler slidable on the conductor and provided with a bridge coperating with the contacts, a hand-piece inclosing said parts and provided with a slot, and a finger-piece slidable on the hand-piece and connected through the slot with the traveler, substantially as described.

4. In a dental instrument the combination of a hand piece, a tool shank detachably connected with the hand piece, a heater de- 1achably mounted in the tool shank and deachable along with the shank from the hand piece, and detachable contacts between the heater and hand piece and respectively attached to the hand piece and heater, substantially as described.

5. In al dental instrument the combina tion of a tubular hand-piece provided with a slot, a conductor provided with spaced blocks having confronting circuit contacts and heater contacts, a traveler having a bridge and movable on the conductor between the confronting contacts, a ring on the hand-piece, and a detachable connection arranged in the slot and connecting the rin and traveler, the conductor and traveler an blocks and their accessories being removable as a unitary structure.

6. In a dental instrument the combination of a tubular hand-piece, a detachable tool' provided with a heater, a finger-piece slidable on the hand-piece, and circuit connections including a switch operable by the hand-piece and contacts automatically disengageable from the heater, substantially as described.

7. In a dental instrument the combination of a hollow hand-piece, and circuit control mechanism insertible and removable as a unit in respect to the hand-piece and comprising a pair of blocks both provided with contacts and one provided with a rheosta-t coil and a conductor connecting said blocks and sliding elements accessible from the outside of the hand-piece and coperating with the contacts to close and open circuit, and with the rheostat coil to regulate circuit, substantially as described.

JAMES ERNEST REID. CHARLES KIENLE. 

